[ViewVC] Diff of: cvs/IO-AIO/AIO.pm

Comparing IO-AIO/AIO.pm (file contents):
Revision 1.165 by root, Tue Aug 18 04:05:00 2009 UTC vs.
Revision 1.208 by root, Mon Sep 26 20:19:08 2011 UTC

…		…
4		4
5	=head1 SYNOPSIS	5	=head1 SYNOPSIS
6		6
7	use IO::AIO;	7	use IO::AIO;
8		8
9	aio_open "/etc/passwd", O_RDONLY, 0, sub {	9	aio_open "/etc/passwd", IO::AIO::O_RDONLY, 0, sub {
10	my $fh = shift	10	my $fh = shift
11	or die "/etc/passwd: $!";	11	or die "/etc/passwd: $!";
12	...	12	...
13	};	13	};
14		14
…		…
25	my $req = aio_unlink "/tmp/file", sub { };	25	my $req = aio_unlink "/tmp/file", sub { };
26	$req->cancel; # cancel request if still in queue	26	$req->cancel; # cancel request if still in queue
27		27
28	my $grp = aio_group sub { print "all stats done\n" };	28	my $grp = aio_group sub { print "all stats done\n" };
29	add $grp aio_stat "..." for ...;	29	add $grp aio_stat "..." for ...;
30
31	# AnyEvent integration (EV, Event, Glib, Tk, POE, urxvt, pureperl...)
32	use AnyEvent::AIO;
33
34	# EV integration
35	my $aio_w = EV::io IO::AIO::poll_fileno, EV::READ, \&IO::AIO::poll_cb;
36
37	# Event integration
38	Event->io (fd => IO::AIO::poll_fileno,
39	poll => 'r',
40	cb => \&IO::AIO::poll_cb);
41
42	# Glib/Gtk2 integration
43	add_watch Glib::IO IO::AIO::poll_fileno,
44	in => sub { IO::AIO::poll_cb; 1 };
45
46	# Tk integration
47	Tk::Event::IO->fileevent (IO::AIO::poll_fileno, "",
48	readable => \&IO::AIO::poll_cb);
49
50	# Danga::Socket integration
51	Danga::Socket->AddOtherFds (IO::AIO::poll_fileno =>
52	\&IO::AIO::poll_cb);
53		30
54	=head1 DESCRIPTION	31	=head1 DESCRIPTION
55		32
56	This module implements asynchronous I/O using whatever means your	33	This module implements asynchronous I/O using whatever means your
57	operating system supports. It is implemented as an interface to C<libeio>	34	operating system supports. It is implemented as an interface to C<libeio>
…		…
99		76
100	# register the IO::AIO callback with EV	77	# register the IO::AIO callback with EV
101	my $aio_w = EV::io IO::AIO::poll_fileno, EV::READ, \&IO::AIO::poll_cb;	78	my $aio_w = EV::io IO::AIO::poll_fileno, EV::READ, \&IO::AIO::poll_cb;
102		79
103	# queue the request to open /etc/passwd	80	# queue the request to open /etc/passwd
104	aio_open "/etc/passwd", O_RDONLY, 0, sub {	81	aio_open "/etc/passwd", IO::AIO::O_RDONLY, 0, sub {
105	my $fh = shift	82	my $fh = shift
106	or die "error while opening: $!";	83	or die "error while opening: $!";
107		84
108	# stat'ing filehandles is generally non-blocking	85	# stat'ing filehandles is generally non-blocking
109	my $size = -s $fh;	86	my $size = -s $fh;
…		…
191	use common::sense;	168	use common::sense;
192		169
193	use base 'Exporter';	170	use base 'Exporter';
194		171
195	BEGIN {	172	BEGIN {
196	our $VERSION = '3.3';	173	our $VERSION = '4.0';
197		174
198	our @AIO_REQ = qw(aio_sendfile aio_read aio_write aio_open aio_close	175	our @AIO_REQ = qw(aio_sendfile aio_read aio_write aio_open aio_close
199	aio_stat aio_lstat aio_unlink aio_rmdir aio_readdir aio_readdirx	176	aio_stat aio_lstat aio_unlink aio_rmdir aio_readdir aio_readdirx
200	aio_scandir aio_symlink aio_readlink aio_sync aio_fsync	177	aio_scandir aio_symlink aio_readlink aio_realpath aio_sync
201	aio_fdatasync aio_sync_file_range aio_pathsync aio_readahead	178	aio_fsync aio_syncfs aio_fdatasync aio_sync_file_range aio_fallocate
		179	aio_pathsync aio_readahead
202	aio_rename aio_link aio_move aio_copy aio_group	180	aio_rename aio_link aio_move aio_copy aio_group
203	aio_nop aio_mknod aio_load aio_rmtree aio_mkdir aio_chown	181	aio_nop aio_mknod aio_load aio_rmtree aio_mkdir aio_chown
204	aio_chmod aio_utime aio_truncate);	182	aio_chmod aio_utime aio_truncate
		183	aio_msync aio_mtouch aio_mlock aio_mlockall
		184	aio_statvfs
		185	aio_wd);
205		186
206	our @EXPORT = (@AIO_REQ, qw(aioreq_pri aioreq_nice));	187	our @EXPORT = (@AIO_REQ, qw(aioreq_pri aioreq_nice));
207	our @EXPORT_OK = qw(poll_fileno poll_cb poll_wait flush	188	our @EXPORT_OK = qw(poll_fileno poll_cb poll_wait flush
208	min_parallel max_parallel max_idle	189	min_parallel max_parallel max_idle idle_timeout
209	nreqs nready npending nthreads	190	nreqs nready npending nthreads
210	max_poll_time max_poll_reqs	191	max_poll_time max_poll_reqs
211	sendfile fadvise);	192	sendfile fadvise madvise
		193	mmap munmap munlock munlockall);
212		194
213	push @AIO_REQ, qw(aio_busy); # not exported	195	push @AIO_REQ, qw(aio_busy); # not exported
214		196
215	@IO::AIO::GRP::ISA = 'IO::AIO::REQ';	197	@IO::AIO::GRP::ISA = 'IO::AIO::REQ';
216		198
217	require XSLoader;	199	require XSLoader;
218	XSLoader::load ("IO::AIO", $VERSION);	200	XSLoader::load ("IO::AIO", $VERSION);
219	}	201	}
220		202
221	=head1 FUNCTIONS	203	=head1 FUNCTIONS
		204
		205	=head2 QUICK OVERVIEW
		206
		207	This section simply lists the prototypes of the most important functions
		208	for quick reference. See the following sections for function-by-function
		209	documentation.
		210
		211	aio_wd $pathname, $callback->($wd)
		212	aio_open $pathname, $flags, $mode, $callback->($fh)
		213	aio_close $fh, $callback->($status)
		214	aio_read $fh,$offset,$length, $data,$dataoffset, $callback->($retval)
		215	aio_write $fh,$offset,$length, $data,$dataoffset, $callback->($retval)
		216	aio_sendfile $out_fh, $in_fh, $in_offset, $length, $callback->($retval)
		217	aio_readahead $fh,$offset,$length, $callback->($retval)
		218	aio_stat $fh_or_path, $callback->($status)
		219	aio_lstat $fh, $callback->($status)
		220	aio_statvfs $fh_or_path, $callback->($statvfs)
		221	aio_utime $fh_or_path, $atime, $mtime, $callback->($status)
		222	aio_chown $fh_or_path, $uid, $gid, $callback->($status)
		223	aio_truncate $fh_or_path, $offset, $callback->($status)
		224	aio_chmod $fh_or_path, $mode, $callback->($status)
		225	aio_unlink $pathname, $callback->($status)
		226	aio_mknod $path, $mode, $dev, $callback->($status)
		227	aio_link $srcpath, $dstpath, $callback->($status)
		228	aio_symlink $srcpath, $dstpath, $callback->($status)
		229	aio_readlink $path, $callback->($link)
		230	aio_realpath $path, $callback->($link)
		231	aio_rename $srcpath, $dstpath, $callback->($status)
		232	aio_mkdir $pathname, $mode, $callback->($status)
		233	aio_rmdir $pathname, $callback->($status)
		234	aio_readdir $pathname, $callback->($entries)
		235	aio_readdirx $pathname, $flags, $callback->($entries, $flags)
		236	IO::AIO::READDIR_DENTS IO::AIO::READDIR_DIRS_FIRST
		237	IO::AIO::READDIR_STAT_ORDER IO::AIO::READDIR_FOUND_UNKNOWN
		238	aio_load $path, $data, $callback->($status)
		239	aio_copy $srcpath, $dstpath, $callback->($status)
		240	aio_move $srcpath, $dstpath, $callback->($status)
		241	aio_scandir $path, $maxreq, $callback->($dirs, $nondirs)
		242	aio_rmtree $path, $callback->($status)
		243	aio_sync $callback->($status)
		244	aio_syncfs $fh, $callback->($status)
		245	aio_fsync $fh, $callback->($status)
		246	aio_fdatasync $fh, $callback->($status)
		247	aio_sync_file_range $fh, $offset, $nbytes, $flags, $callback->($status)
		248	aio_pathsync $path, $callback->($status)
		249	aio_msync $scalar, $offset = 0, $length = undef, flags = 0, $callback->($status)
		250	aio_mtouch $scalar, $offset = 0, $length = undef, flags = 0, $callback->($status)
		251	aio_mlock $scalar, $offset = 0, $length = undef, $callback->($status)
		252	aio_mlockall $flags, $callback->($status)
		253	aio_group $callback->(...)
		254	aio_nop $callback->()
		255
		256	$prev_pri = aioreq_pri [$pri]
		257	aioreq_nice $pri_adjust
		258
		259	IO::AIO::poll_wait
		260	IO::AIO::poll_cb
		261	IO::AIO::poll
		262	IO::AIO::flush
		263	IO::AIO::max_poll_reqs $nreqs
		264	IO::AIO::max_poll_time $seconds
		265	IO::AIO::min_parallel $nthreads
		266	IO::AIO::max_parallel $nthreads
		267	IO::AIO::max_idle $nthreads
		268	IO::AIO::idle_timeout $seconds
		269	IO::AIO::max_outstanding $maxreqs
		270	IO::AIO::nreqs
		271	IO::AIO::nready
		272	IO::AIO::npending
		273
		274	IO::AIO::sendfile $ofh, $ifh, $offset, $count
		275	IO::AIO::fadvise $fh, $offset, $len, $advice
		276	IO::AIO::madvise $scalar, $offset, $length, $advice
		277	IO::AIO::mprotect $scalar, $offset, $length, $protect
		278	IO::AIO::munlock $scalar, $offset = 0, $length = undef
		279	IO::AIO::munlockall
222		280
223	=head2 AIO REQUEST FUNCTIONS	281	=head2 AIO REQUEST FUNCTIONS
224		282
225	All the C<aio_*> calls are more or less thin wrappers around the syscall	283	All the C<aio_*> calls are more or less thin wrappers around the syscall
226	with the same name (sans C<aio_>). The arguments are similar or identical,	284	with the same name (sans C<aio_>). The arguments are similar or identical,
…		…
306	by the umask in effect then the request is being executed, so better never	364	by the umask in effect then the request is being executed, so better never
307	change the umask.	365	change the umask.
308		366
309	Example:	367	Example:
310		368
311	aio_open "/etc/passwd", O_RDONLY, 0, sub {	369	aio_open "/etc/passwd", IO::AIO::O_RDONLY, 0, sub {
312	if ($_[0]) {	370	if ($_[0]) {
313	print "open successful, fh is $_[0]\n";	371	print "open successful, fh is $_[0]\n";
314	...	372	...
315	} else {	373	} else {
316	die "open failed: $!\n";	374	die "open failed: $!\n";
317	}	375	}
318	};	376	};
319		377
		378	In addition to all the common open modes/flags (C<O_RDONLY>, C<O_WRONLY>,
		379	C<O_RDWR>, C<O_CREAT>, C<O_TRUNC>, C<O_EXCL> and C<O_APPEND>), the
		380	following POSIX and non-POSIX constants are available (missing ones on
		381	your system are, as usual, C<0>):
		382
		383	C<O_ASYNC>, C<O_DIRECT>, C<O_NOATIME>, C<O_CLOEXEC>, C<O_NOCTTY>, C<O_NOFOLLOW>,
		384	C<O_NONBLOCK>, C<O_EXEC>, C<O_SEARCH>, C<O_DIRECTORY>, C<O_DSYNC>,
		385	C<O_RSYNC>, C<O_SYNC> and C<O_TTY_INIT>.
		386
320		387
321	=item aio_close $fh, $callback->($status)	388	=item aio_close $fh, $callback->($status)
322		389
323	Asynchronously close a file and call the callback with the result	390	Asynchronously close a file and call the callback with the result
324	code.	391	code.
…		…
374		441
375	Tries to copy C<$length> bytes from C<$in_fh> to C<$out_fh>. It starts	442	Tries to copy C<$length> bytes from C<$in_fh> to C<$out_fh>. It starts
376	reading at byte offset C<$in_offset>, and starts writing at the current	443	reading at byte offset C<$in_offset>, and starts writing at the current
377	file offset of C<$out_fh>. Because of that, it is not safe to issue more	444	file offset of C<$out_fh>. Because of that, it is not safe to issue more
378	than one C<aio_sendfile> per C<$out_fh>, as they will interfere with each	445	than one C<aio_sendfile> per C<$out_fh>, as they will interfere with each
379	other.	446	other. The same C<$in_fh> works fine though, as this function does not
		447	move or use the file offset of C<$in_fh>.
380		448
		449	Please note that C<aio_sendfile> can read more bytes from C<$in_fh> than
		450	are written, and there is no way to find out how many more bytes have been
		451	read from C<aio_sendfile> alone, as C<aio_sendfile> only provides the
		452	number of bytes written to C<$out_fh>. Only if the result value equals
		453	C<$length> one can assume that C<$length> bytes have been read.
		454
		455	Unlike with other C<aio_> functions, it makes a lot of sense to use
		456	C<aio_sendfile> on non-blocking sockets, as long as one end (typically
		457	the C<$in_fh>) is a file - the file I/O will then be asynchronous, while
		458	the socket I/O will be non-blocking. Note, however, that you can run
		459	into a trap where C<aio_sendfile> reads some data with readahead, then
		460	fails to write all data, and when the socket is ready the next time, the
		461	data in the cache is already lost, forcing C<aio_sendfile> to again hit
		462	the disk. Explicit C<aio_read> + C<aio_write> let's you better control
		463	resource usage.
		464
381	This call tries to make use of a native C<sendfile> syscall to provide	465	This call tries to make use of a native C<sendfile>-like syscall to
382	zero-copy operation. For this to work, C<$out_fh> should refer to a	466	provide zero-copy operation. For this to work, C<$out_fh> should refer to
383	socket, and C<$in_fh> should refer to mmap'able file.	467	a socket, and C<$in_fh> should refer to an mmap'able file.
384		468
385	If the native sendfile call fails or is not implemented, it will be	469	If a native sendfile cannot be found or it fails with C<ENOSYS>,
386	emulated, so you can call C<aio_sendfile> on any type of filehandle	470	C<EINVAL>, C<ENOTSUP>, C<EOPNOTSUPP>, C<EAFNOSUPPORT>, C<EPROTOTYPE> or
		471	C<ENOTSOCK>, it will be emulated, so you can call C<aio_sendfile> on any
387	regardless of the limitations of the operating system.	472	type of filehandle regardless of the limitations of the operating system.
388		473
389	Please note, however, that C<aio_sendfile> can read more bytes from	474	As native sendfile syscalls (as practically any non-POSIX interface hacked
390	C<$in_fh> than are written, and there is no way to find out how many	475	together in a hurry to improve benchmark numbers) tend to be rather buggy
391	bytes have been read from C<aio_sendfile> alone, as C<aio_sendfile> only	476	on many systems, this implementation tries to work around some known bugs
392	provides the number of bytes written to C<$out_fh>. Only if the result	477	in Linux and FreeBSD kernels (probably others, too), but that might fail,
393	value equals C<$length> one can assume that C<$length> bytes have been	478	so you really really should check the return value of C<aio_sendfile> -
394	read.	479	fewre bytes than expected might have been transferred.
395		480
396		481
397	=item aio_readahead $fh,$offset,$length, $callback->($retval)	482	=item aio_readahead $fh,$offset,$length, $callback->($retval)
398		483
399	C<aio_readahead> populates the page cache with data from a file so that	484	C<aio_readahead> populates the page cache with data from a file so that
…		…
422		507
423	Currently, the stats are always 64-bit-stats, i.e. instead of returning an	508	Currently, the stats are always 64-bit-stats, i.e. instead of returning an
424	error when stat'ing a large file, the results will be silently truncated	509	error when stat'ing a large file, the results will be silently truncated
425	unless perl itself is compiled with large file support.	510	unless perl itself is compiled with large file support.
426		511
		512	To help interpret the mode and dev/rdev stat values, IO::AIO offers the
		513	following constants and functions (if not implemented, the constants will
		514	be C<0> and the functions will either C<croak> or fall back on traditional
		515	behaviour).
		516
		517	C<S_IFMT>, C<S_IFIFO>, C<S_IFCHR>, C<S_IFBLK>, C<S_IFLNK>, C<S_IFREG>,
		518	C<S_IFDIR>, C<S_IFWHT>, C<S_IFSOCK>, C<IO::AIO::major $dev_t>,
		519	C<IO::AIO::minor $dev_t>, C<IO::AIO::makedev $major, $minor>.
		520
427	Example: Print the length of F</etc/passwd>:	521	Example: Print the length of F</etc/passwd>:
428		522
429	aio_stat "/etc/passwd", sub {	523	aio_stat "/etc/passwd", sub {
430	$_[0] and die "stat failed: $!";	524	$_[0] and die "stat failed: $!";
431	print "size is ", -s _, "\n";	525	print "size is ", -s _, "\n";
432	};	526	};
433		527
434		528
		529	=item aio_statvfs $fh_or_path, $callback->($statvfs)
		530
		531	Works like the POSIX C<statvfs> or C<fstatvfs> syscalls, depending on
		532	whether a file handle or path was passed.
		533
		534	On success, the callback is passed a hash reference with the following
		535	members: C<bsize>, C<frsize>, C<blocks>, C<bfree>, C<bavail>, C<files>,
		536	C<ffree>, C<favail>, C<fsid>, C<flag> and C<namemax>. On failure, C<undef>
		537	is passed.
		538
		539	The following POSIX IO::AIO::ST_* constants are defined: C<ST_RDONLY> and
		540	C<ST_NOSUID>.
		541
		542	The following non-POSIX IO::AIO::ST_* flag masks are defined to
		543	their correct value when available, or to C<0> on systems that do
		544	not support them: C<ST_NODEV>, C<ST_NOEXEC>, C<ST_SYNCHRONOUS>,
		545	C<ST_MANDLOCK>, C<ST_WRITE>, C<ST_APPEND>, C<ST_IMMUTABLE>, C<ST_NOATIME>,
		546	C<ST_NODIRATIME> and C<ST_RELATIME>.
		547
		548	Example: stat C</wd> and dump out the data if successful.
		549
		550	aio_statvfs "/wd", sub {
		551	my $f = $_[0]
		552	or die "statvfs: $!";
		553
		554	use Data::Dumper;
		555	say Dumper $f;
		556	};
		557
		558	# result:
		559	{
		560	bsize => 1024,
		561	bfree => 4333064312,
		562	blocks => 10253828096,
		563	files => 2050765568,
		564	flag => 4096,
		565	favail => 2042092649,
		566	bavail => 4333064312,
		567	ffree => 2042092649,
		568	namemax => 255,
		569	frsize => 1024,
		570	fsid => 1810
		571	}
		572
		573
435	=item aio_utime $fh_or_path, $atime, $mtime, $callback->($status)	574	=item aio_utime $fh_or_path, $atime, $mtime, $callback->($status)
436		575
437	Works like perl's C<utime> function (including the special case of $atime	576	Works like perl's C<utime> function (including the special case of $atime
438	and $mtime being undef). Fractional times are supported if the underlying	577	and $mtime being undef). Fractional times are supported if the underlying
439	syscalls support them.	578	syscalls support them.
…		…
487		626
488	The only (POSIX-) portable way of calling this function is:	627	The only (POSIX-) portable way of calling this function is:
489		628
490	aio_mknod $path, IO::AIO::S_IFIFO \| $mode, 0, sub { ...	629	aio_mknod $path, IO::AIO::S_IFIFO \| $mode, 0, sub { ...
491		630
		631	See C<aio_stat> for info about some potentially helpful extra constants
		632	and functions.
492		633
493	=item aio_link $srcpath, $dstpath, $callback->($status)	634	=item aio_link $srcpath, $dstpath, $callback->($status)
494		635
495	Asynchronously create a new link to the existing object at C<$srcpath> at	636	Asynchronously create a new link to the existing object at C<$srcpath> at
496	the path C<$dstpath> and call the callback with the result code.	637	the path C<$dstpath> and call the callback with the result code.
…		…
507	Asynchronously read the symlink specified by C<$path> and pass it to	648	Asynchronously read the symlink specified by C<$path> and pass it to
508	the callback. If an error occurs, nothing or undef gets passed to the	649	the callback. If an error occurs, nothing or undef gets passed to the
509	callback.	650	callback.
510		651
511		652
		653	=item aio_realpath $path, $callback->($path)
		654
		655	Asynchronously make the path absolute and resolve any symlinks in
		656	C<$path>. The resulting path only consists of directories (Same as
		657	L<Cwd::realpath>).
		658
		659	This request can be used to get the absolute path of the current working
		660	directory by passing it a path of F<.> (a single dot).
		661
		662
512	=item aio_rename $srcpath, $dstpath, $callback->($status)	663	=item aio_rename $srcpath, $dstpath, $callback->($status)
513		664
514	Asynchronously rename the object at C<$srcpath> to C<$dstpath>, just as	665	Asynchronously rename the object at C<$srcpath> to C<$dstpath>, just as
515	rename(2) and call the callback with the result code.	666	rename(2) and call the callback with the result code.
516		667
…		…
538	array-ref with the filenames.	689	array-ref with the filenames.
539		690
540		691
541	=item aio_readdirx $pathname, $flags, $callback->($entries, $flags)	692	=item aio_readdirx $pathname, $flags, $callback->($entries, $flags)
542		693
543	Quite similar to C<aio_readdir>, but the C<$flags> argument allows to tune	694	Quite similar to C<aio_readdir>, but the C<$flags> argument allows one to
544	behaviour and output format. In case of an error, C<$entries> will be	695	tune behaviour and output format. In case of an error, C<$entries> will be
545	C<undef>.	696	C<undef>.
546		697
547	The flags are a combination of the following constants, ORed together (the	698	The flags are a combination of the following constants, ORed together (the
548	flags will also be passed to the callback, possibly modified):	699	flags will also be passed to the callback, possibly modified):
549		700
550	=over 4	701	=over 4
551		702
552	=item IO::AIO::READDIR_DENTS	703	=item IO::AIO::READDIR_DENTS
553		704
554	When this flag is off, then the callback gets an arrayref with of names	705	When this flag is off, then the callback gets an arrayref consisting of
555	only (as with C<aio_readdir>), otherwise it gets an arrayref with	706	names only (as with C<aio_readdir>), otherwise it gets an arrayref with
556	C<[$name, $type, $inode]> arrayrefs, each describing a single directory	707	C<[$name, $type, $inode]> arrayrefs, each describing a single directory
557	entry in more detail.	708	entry in more detail.
558		709
559	C<$name> is the name of the entry.	710	C<$name> is the name of the entry.
560		711
…		…
573	systems that do not deliver the inode information.	724	systems that do not deliver the inode information.
574		725
575	=item IO::AIO::READDIR_DIRS_FIRST	726	=item IO::AIO::READDIR_DIRS_FIRST
576		727
577	When this flag is set, then the names will be returned in an order where	728	When this flag is set, then the names will be returned in an order where
578	likely directories come first. This is useful when you need to quickly	729	likely directories come first, in optimal stat order. This is useful when
579	find directories, or you want to find all directories while avoiding to	730	you need to quickly find directories, or you want to find all directories
580	stat() each entry.	731	while avoiding to stat() each entry.
581		732
582	If the system returns type information in readdir, then this is used	733	If the system returns type information in readdir, then this is used
583	to find directories directly. Otherwise, likely directories are files	734	to find directories directly. Otherwise, likely directories are names
584	beginning with ".", or otherwise files with no dots, of which files with	735	beginning with ".", or otherwise names with no dots, of which names with
585	short names are tried first.	736	short names are tried first.
586		737
587	=item IO::AIO::READDIR_STAT_ORDER	738	=item IO::AIO::READDIR_STAT_ORDER
588		739
589	When this flag is set, then the names will be returned in an order	740	When this flag is set, then the names will be returned in an order
…		…
596		747
597	=item IO::AIO::READDIR_FOUND_UNKNOWN	748	=item IO::AIO::READDIR_FOUND_UNKNOWN
598		749
599	This flag should not be set when calling C<aio_readdirx>. Instead, it	750	This flag should not be set when calling C<aio_readdirx>. Instead, it
600	is being set by C<aio_readdirx>, when any of the C<$type>'s found were	751	is being set by C<aio_readdirx>, when any of the C<$type>'s found were
601	C<IO::AIO::DT_UNKNOWN>. The absense of this flag therefore indicates that all	752	C<IO::AIO::DT_UNKNOWN>. The absence of this flag therefore indicates that all
602	C<$type>'s are known, which can be used to speed up some algorithms.	753	C<$type>'s are known, which can be used to speed up some algorithms.
603		754
604	=back	755	=back
605		756
606		757
…		…
656	my $grp = aio_group $cb;	807	my $grp = aio_group $cb;
657		808
658	aioreq_pri $pri;	809	aioreq_pri $pri;
659	add $grp aio_open $src, O_RDONLY, 0, sub {	810	add $grp aio_open $src, O_RDONLY, 0, sub {
660	if (my $src_fh = $_[0]) {	811	if (my $src_fh = $_[0]) {
661	my @stat = stat $src_fh; # hmm, might bock over nfs?	812	my @stat = stat $src_fh; # hmm, might block over nfs?
662		813
663	aioreq_pri $pri;	814	aioreq_pri $pri;
664	add $grp aio_open $dst, O_CREAT \| O_WRONLY \| O_TRUNC, 0200, sub {	815	add $grp aio_open $dst, O_CREAT \| O_WRONLY \| O_TRUNC, 0200, sub {
665	if (my $dst_fh = $_[0]) {	816	if (my $dst_fh = $_[0]) {
666	aioreq_pri $pri;	817	aioreq_pri $pri;
…		…
734	if ($_[0] && $! == EXDEV) {	885	if ($_[0] && $! == EXDEV) {
735	aioreq_pri $pri;	886	aioreq_pri $pri;
736	add $grp aio_copy $src, $dst, sub {	887	add $grp aio_copy $src, $dst, sub {
737	$grp->result ($_[0]);	888	$grp->result ($_[0]);
738		889
739	if (!$_[0]) {	890	unless ($_[0]) {
740	aioreq_pri $pri;	891	aioreq_pri $pri;
741	add $grp aio_unlink $src;	892	add $grp aio_unlink $src;
742	}	893	}
743	};	894	};
744	} else {	895	} else {
…		…
788	Then entries will be sorted into likely directories a non-initial dot	939	Then entries will be sorted into likely directories a non-initial dot
789	currently) and likely non-directories (see C<aio_readdirx>). Then every	940	currently) and likely non-directories (see C<aio_readdirx>). Then every
790	entry plus an appended C</.> will be C<stat>'ed, likely directories first,	941	entry plus an appended C</.> will be C<stat>'ed, likely directories first,
791	in order of their inode numbers. If that succeeds, it assumes that the	942	in order of their inode numbers. If that succeeds, it assumes that the
792	entry is a directory or a symlink to directory (which will be checked	943	entry is a directory or a symlink to directory (which will be checked
793	seperately). This is often faster than stat'ing the entry itself because	944	separately). This is often faster than stat'ing the entry itself because
794	filesystems might detect the type of the entry without reading the inode	945	filesystems might detect the type of the entry without reading the inode
795	data (e.g. ext2fs filetype feature), even on systems that cannot return	946	data (e.g. ext2fs filetype feature), even on systems that cannot return
796	the filetype information on readdir.	947	the filetype information on readdir.
797		948
798	If the known number of directories (link count - 2) has been reached, the	949	If the known number of directories (link count - 2) has been reached, the
…		…
936	callback with the fdatasync result code.	1087	callback with the fdatasync result code.
937		1088
938	If this call isn't available because your OS lacks it or it couldn't be	1089	If this call isn't available because your OS lacks it or it couldn't be
939	detected, it will be emulated by calling C<fsync> instead.	1090	detected, it will be emulated by calling C<fsync> instead.
940		1091
		1092	=item aio_syncfs $fh, $callback->($status)
		1093
		1094	Asynchronously call the syncfs syscall to sync the filesystem associated
		1095	to the given filehandle and call the callback with the syncfs result
		1096	code. If syncfs is not available, calls sync(), but returns C<-1> and sets
		1097	errno to C<ENOSYS> nevertheless.
		1098
941	=item aio_sync_file_range $fh, $offset, $nbytes, $flags, $callback->($status)	1099	=item aio_sync_file_range $fh, $offset, $nbytes, $flags, $callback->($status)
942		1100
943	Sync the data portion of the file specified by C<$offset> and C<$length>	1101	Sync the data portion of the file specified by C<$offset> and C<$length>
944	to disk (but NOT the metadata), by calling the Linux-specific	1102	to disk (but NOT the metadata), by calling the Linux-specific
945	sync_file_range call. If sync_file_range is not available or it returns	1103	sync_file_range call. If sync_file_range is not available or it returns
…		…
989	};	1147	};
990		1148
991	$grp	1149	$grp
992	}	1150	}
993		1151
		1152	=item aio_msync $scalar, $offset = 0, $length = undef, flags = 0, $callback->($status)
		1153
		1154	This is a rather advanced IO::AIO call, which only works on mmap(2)ed
		1155	scalars (see the C<IO::AIO::mmap> function, although it also works on data
		1156	scalars managed by the L<Sys::Mmap> or L<Mmap> modules, note that the
		1157	scalar must only be modified in-place while an aio operation is pending on
		1158	it).
		1159
		1160	It calls the C<msync> function of your OS, if available, with the memory
		1161	area starting at C<$offset> in the string and ending C<$length> bytes
		1162	later. If C<$length> is negative, counts from the end, and if C<$length>
		1163	is C<undef>, then it goes till the end of the string. The flags can be
		1164	a combination of C<IO::AIO::MS_ASYNC>, C<IO::AIO::MS_INVALIDATE> and
		1165	C<IO::AIO::MS_SYNC>.
		1166
		1167	=item aio_mtouch $scalar, $offset = 0, $length = undef, flags = 0, $callback->($status)
		1168
		1169	This is a rather advanced IO::AIO call, which works best on mmap(2)ed
		1170	scalars.
		1171
		1172	It touches (reads or writes) all memory pages in the specified
		1173	range inside the scalar. All caveats and parameters are the same
		1174	as for C<aio_msync>, above, except for flags, which must be either
		1175	C<0> (which reads all pages and ensures they are instantiated) or
		1176	C<IO::AIO::MT_MODIFY>, which modifies the memory page s(by reading and
		1177	writing an octet from it, which dirties the page).
		1178
		1179	=item aio_mlock $scalar, $offset = 0, $length = undef, $callback->($status)
		1180
		1181	This is a rather advanced IO::AIO call, which works best on mmap(2)ed
		1182	scalars.
		1183
		1184	It reads in all the pages of the underlying storage into memory (if any)
		1185	and locks them, so they are not getting swapped/paged out or removed.
		1186
		1187	If C<$length> is undefined, then the scalar will be locked till the end.
		1188
		1189	On systems that do not implement C<mlock>, this function returns C<-1>
		1190	and sets errno to C<ENOSYS>.
		1191
		1192	Note that the corresponding C<munlock> is synchronous and is
		1193	documented under L<MISCELLANEOUS FUNCTIONS>.
		1194
		1195	Example: open a file, mmap and mlock it - both will be undone when
		1196	C<$data> gets destroyed.
		1197
		1198	open my $fh, "<", $path or die "$path: $!";
		1199	my $data;
		1200	IO::AIO::mmap $data, -s $fh, IO::AIO::PROT_READ, IO::AIO::MAP_SHARED, $fh;
		1201	aio_mlock $data; # mlock in background
		1202
		1203	=item aio_mlockall $flags, $callback->($status)
		1204
		1205	Calls the C<mlockall> function with the given C<$flags> (a combination of
		1206	C<IO::AIO::MCL_CURRENT> and C<IO::AIO::MCL_FUTURE>).
		1207
		1208	On systems that do not implement C<mlockall>, this function returns C<-1>
		1209	and sets errno to C<ENOSYS>.
		1210
		1211	Note that the corresponding C<munlockall> is synchronous and is
		1212	documented under L<MISCELLANEOUS FUNCTIONS>.
		1213
		1214	Example: asynchronously lock all current and future pages into memory.
		1215
		1216	aio_mlockall IO::AIO::MCL_FUTURE;
		1217
994	=item aio_group $callback->(...)	1218	=item aio_group $callback->(...)
995		1219
996	This is a very special aio request: Instead of doing something, it is a	1220	This is a very special aio request: Instead of doing something, it is a
997	container for other aio requests, which is useful if you want to bundle	1221	container for other aio requests, which is useful if you want to bundle
998	many requests into a single, composite, request with a definite callback	1222	many requests into a single, composite, request with a definite callback
…		…
1133	=item $grp->cancel_subs	1357	=item $grp->cancel_subs
1134		1358
1135	Cancel all subrequests and clears any feeder, but not the group request	1359	Cancel all subrequests and clears any feeder, but not the group request
1136	itself. Useful when you queued a lot of events but got a result early.	1360	itself. Useful when you queued a lot of events but got a result early.
1137		1361
		1362	The group request will finish normally (you cannot add requests to the
		1363	group).
		1364
1138	=item $grp->result (...)	1365	=item $grp->result (...)
1139		1366
1140	Set the result value(s) that will be passed to the group callback when all	1367	Set the result value(s) that will be passed to the group callback when all
1141	subrequests have finished and set the groups errno to the current value	1368	subrequests have finished and set the groups errno to the current value
1142	of errno (just like calling C<errno> without an error number). By default,	1369	of errno (just like calling C<errno> without an error number). By default,
…		…
1218		1445
1219	See C<poll_cb> for an example.	1446	See C<poll_cb> for an example.
1220		1447
1221	=item IO::AIO::poll_cb	1448	=item IO::AIO::poll_cb
1222		1449
1223	Process some outstanding events on the result pipe. You have to call this	1450	Process some outstanding events on the result pipe. You have to call
1224	regularly. Returns C<0> if all events could be processed, or C<-1> if it	1451	this regularly. Returns C<0> if all events could be processed (or there
1225	returned earlier for whatever reason. Returns immediately when no events	1452	were no events to process), or C<-1> if it returned earlier for whatever
1226	are outstanding. The amount of events processed depends on the settings of	1453	reason. Returns immediately when no events are outstanding. The amount of
1227	C<IO::AIO::max_poll_req> and C<IO::AIO::max_poll_time>.	1454	events processed depends on the settings of C<IO::AIO::max_poll_req> and
		1455	C<IO::AIO::max_poll_time>.
1228		1456
1229	If not all requests were processed for whatever reason, the filehandle	1457	If not all requests were processed for whatever reason, the filehandle
1230	will still be ready when C<poll_cb> returns, so normally you don't have to	1458	will still be ready when C<poll_cb> returns, so normally you don't have to
1231	do anything special to have it called later.	1459	do anything special to have it called later.
1232		1460
		1461	Apart from calling C<IO::AIO::poll_cb> when the event filehandle becomes
		1462	ready, it can be beneficial to call this function from loops which submit
		1463	a lot of requests, to make sure the results get processed when they become
		1464	available and not just when the loop is finished and the event loop takes
		1465	over again. This function returns very fast when there are no outstanding
		1466	requests.
		1467
1233	Example: Install an Event watcher that automatically calls	1468	Example: Install an Event watcher that automatically calls
1234	IO::AIO::poll_cb with high priority (more examples can be found in the	1469	IO::AIO::poll_cb with high priority (more examples can be found in the
1235	SYNOPSIS section, at the top of this document):	1470	SYNOPSIS section, at the top of this document):
1236		1471
1237	Event->io (fd => IO::AIO::poll_fileno,	1472	Event->io (fd => IO::AIO::poll_fileno,
1238	poll => 'r', async => 1,	1473	poll => 'r', async => 1,
1239	cb => \&IO::AIO::poll_cb);	1474	cb => \&IO::AIO::poll_cb);
		1475
		1476	=item IO::AIO::poll_wait
		1477
		1478	If there are any outstanding requests and none of them in the result
		1479	phase, wait till the result filehandle becomes ready for reading (simply
		1480	does a C<select> on the filehandle. This is useful if you want to
		1481	synchronously wait for some requests to finish).
		1482
		1483	See C<nreqs> for an example.
		1484
		1485	=item IO::AIO::poll
		1486
		1487	Waits until some requests have been handled.
		1488
		1489	Returns the number of requests processed, but is otherwise strictly
		1490	equivalent to:
		1491
		1492	IO::AIO::poll_wait, IO::AIO::poll_cb
		1493
		1494	=item IO::AIO::flush
		1495
		1496	Wait till all outstanding AIO requests have been handled.
		1497
		1498	Strictly equivalent to:
		1499
		1500	IO::AIO::poll_wait, IO::AIO::poll_cb
		1501	while IO::AIO::nreqs;
1240		1502
1241	=item IO::AIO::max_poll_reqs $nreqs	1503	=item IO::AIO::max_poll_reqs $nreqs
1242		1504
1243	=item IO::AIO::max_poll_time $seconds	1505	=item IO::AIO::max_poll_time $seconds
1244		1506
…		…
1269	# use a low priority so other tasks have priority	1531	# use a low priority so other tasks have priority
1270	Event->io (fd => IO::AIO::poll_fileno,	1532	Event->io (fd => IO::AIO::poll_fileno,
1271	poll => 'r', nice => 1,	1533	poll => 'r', nice => 1,
1272	cb => &IO::AIO::poll_cb);	1534	cb => &IO::AIO::poll_cb);
1273		1535
1274	=item IO::AIO::poll_wait
1275
1276	If there are any outstanding requests and none of them in the result
1277	phase, wait till the result filehandle becomes ready for reading (simply
1278	does a C<select> on the filehandle. This is useful if you want to
1279	synchronously wait for some requests to finish).
1280
1281	See C<nreqs> for an example.
1282
1283	=item IO::AIO::poll
1284
1285	Waits until some requests have been handled.
1286
1287	Returns the number of requests processed, but is otherwise strictly
1288	equivalent to:
1289
1290	IO::AIO::poll_wait, IO::AIO::poll_cb
1291
1292	=item IO::AIO::flush
1293
1294	Wait till all outstanding AIO requests have been handled.
1295
1296	Strictly equivalent to:
1297
1298	IO::AIO::poll_wait, IO::AIO::poll_cb
1299	while IO::AIO::nreqs;
1300
1301	=back	1536	=back
1302		1537
1303	=head3 CONTROLLING THE NUMBER OF THREADS	1538	=head3 CONTROLLING THE NUMBER OF THREADS
1304		1539
1305	=over	1540	=over
…		…
1338		1573
1339	Under normal circumstances you don't need to call this function.	1574	Under normal circumstances you don't need to call this function.
1340		1575
1341	=item IO::AIO::max_idle $nthreads	1576	=item IO::AIO::max_idle $nthreads
1342		1577
1343	Limit the number of threads (default: 4) that are allowed to idle (i.e.,	1578	Limit the number of threads (default: 4) that are allowed to idle
1344	threads that did not get a request to process within 10 seconds). That	1579	(i.e., threads that did not get a request to process within the idle
1345	means if a thread becomes idle while C<$nthreads> other threads are also	1580	timeout (default: 10 seconds). That means if a thread becomes idle while
1346	idle, it will free its resources and exit.	1581	C<$nthreads> other threads are also idle, it will free its resources and
		1582	exit.
1347		1583
1348	This is useful when you allow a large number of threads (e.g. 100 or 1000)	1584	This is useful when you allow a large number of threads (e.g. 100 or 1000)
1349	to allow for extremely high load situations, but want to free resources	1585	to allow for extremely high load situations, but want to free resources
1350	under normal circumstances (1000 threads can easily consume 30MB of RAM).	1586	under normal circumstances (1000 threads can easily consume 30MB of RAM).
1351		1587
1352	The default is probably ok in most situations, especially if thread	1588	The default is probably ok in most situations, especially if thread
1353	creation is fast. If thread creation is very slow on your system you might	1589	creation is fast. If thread creation is very slow on your system you might
1354	want to use larger values.	1590	want to use larger values.
1355		1591
		1592	=item IO::AIO::idle_timeout $seconds
		1593
		1594	Sets the minimum idle timeout (default 10) after which worker threads are
		1595	allowed to exit. SEe C<IO::AIO::max_idle>.
		1596
1356	=item IO::AIO::max_outstanding $maxreqs	1597	=item IO::AIO::max_outstanding $maxreqs
		1598
		1599	Sets the maximum number of outstanding requests to C<$nreqs>. If
		1600	you do queue up more than this number of requests, the next call to
		1601	C<IO::AIO::poll_cb> (and other functions calling C<poll_cb>, such as
		1602	C<IO::AIO::flush> or C<IO::AIO::poll>) will block until the limit is no
		1603	longer exceeded.
		1604
		1605	In other words, this setting does not enforce a queue limit, but can be
		1606	used to make poll functions block if the limit is exceeded.
1357		1607
1358	This is a very bad function to use in interactive programs because it	1608	This is a very bad function to use in interactive programs because it
1359	blocks, and a bad way to reduce concurrency because it is inexact: Better	1609	blocks, and a bad way to reduce concurrency because it is inexact: Better
1360	use an C<aio_group> together with a feed callback.	1610	use an C<aio_group> together with a feed callback.
1361		1611
1362	Sets the maximum number of outstanding requests to C<$nreqs>. If you	1612	It's main use is in scripts without an event loop - when you want to stat
1363	do queue up more than this number of requests, the next call to the	1613	a lot of files, you can write somehting like this:
1364	C<poll_cb> (and C<poll_some> and other functions calling C<poll_cb>)
1365	function will block until the limit is no longer exceeded.
1366		1614
1367	The default value is very large, so there is no practical limit on the	1615	IO::AIO::max_outstanding 32;
1368	number of outstanding requests.
1369		1616
1370	You can still queue as many requests as you want. Therefore,	1617	for my $path (...) {
1371	C<max_outstanding> is mainly useful in simple scripts (with low values) or	1618	aio_stat $path , ...;
1372	as a stop gap to shield against fatal memory overflow (with large values).	1619	IO::AIO::poll_cb;
		1620	}
		1621
		1622	IO::AIO::flush;
		1623
		1624	The call to C<poll_cb> inside the loop will normally return instantly, but
		1625	as soon as more thna C<32> reqeusts are in-flight, it will block until
		1626	some requests have been handled. This keeps the loop from pushing a large
		1627	number of C<aio_stat> requests onto the queue.
		1628
		1629	The default value for C<max_outstanding> is very large, so there is no
		1630	practical limit on the number of outstanding requests.
1373		1631
1374	=back	1632	=back
1375		1633
1376	=head3 STATISTICAL INFORMATION	1634	=head3 STATISTICAL INFORMATION
1377		1635
…		…
1415		1673
1416	Returns the number of bytes copied, or C<-1> on error.	1674	Returns the number of bytes copied, or C<-1> on error.
1417		1675
1418	=item IO::AIO::fadvise $fh, $offset, $len, $advice	1676	=item IO::AIO::fadvise $fh, $offset, $len, $advice
1419		1677
1420	Simply calls the C<posix_fadvise> function (see it's	1678	Simply calls the C<posix_fadvise> function (see its
1421	manpage for details). The following advice constants are	1679	manpage for details). The following advice constants are
1422	avaiable: C<IO::AIO::FADV_NORMAL>, C<IO::AIO::FADV_SEQUENTIAL>,	1680	available: C<IO::AIO::FADV_NORMAL>, C<IO::AIO::FADV_SEQUENTIAL>,
1423	C<IO::AIO::FADV_RANDOM>, C<IO::AIO::FADV_NOREUSE>,	1681	C<IO::AIO::FADV_RANDOM>, C<IO::AIO::FADV_NOREUSE>,
1424	C<IO::AIO::FADV_WILLNEED>, C<IO::AIO::FADV_DONTNEED>.	1682	C<IO::AIO::FADV_WILLNEED>, C<IO::AIO::FADV_DONTNEED>.
1425		1683
1426	On systems that do not implement C<posix_fadvise>, this function returns	1684	On systems that do not implement C<posix_fadvise>, this function returns
1427	ENOSYS, otherwise the return value of C<posix_fadvise>.	1685	ENOSYS, otherwise the return value of C<posix_fadvise>.
1428		1686
		1687	=item IO::AIO::madvise $scalar, $offset, $len, $advice
		1688
		1689	Simply calls the C<posix_madvise> function (see its
		1690	manpage for details). The following advice constants are
		1691	available: C<IO::AIO::MADV_NORMAL>, C<IO::AIO::MADV_SEQUENTIAL>,
		1692	C<IO::AIO::MADV_RANDOM>, C<IO::AIO::MADV_WILLNEED>, C<IO::AIO::MADV_DONTNEED>.
		1693
		1694	On systems that do not implement C<posix_madvise>, this function returns
		1695	ENOSYS, otherwise the return value of C<posix_madvise>.
		1696
		1697	=item IO::AIO::mprotect $scalar, $offset, $len, $protect
		1698
		1699	Simply calls the C<mprotect> function on the preferably AIO::mmap'ed
		1700	$scalar (see its manpage for details). The following protect
		1701	constants are available: C<IO::AIO::PROT_NONE>, C<IO::AIO::PROT_READ>,
		1702	C<IO::AIO::PROT_WRITE>, C<IO::AIO::PROT_EXEC>.
		1703
		1704	On systems that do not implement C<mprotect>, this function returns
		1705	ENOSYS, otherwise the return value of C<mprotect>.
		1706
		1707	=item IO::AIO::mmap $scalar, $length, $prot, $flags, $fh[, $offset]
		1708
		1709	Memory-maps a file (or anonymous memory range) and attaches it to the
		1710	given C<$scalar>, which will act like a string scalar.
		1711
		1712	The only operations allowed on the scalar are C<substr>/C<vec> that don't
		1713	change the string length, and most read-only operations such as copying it
		1714	or searching it with regexes and so on.
		1715
		1716	Anything else is unsafe and will, at best, result in memory leaks.
		1717
		1718	The memory map associated with the C<$scalar> is automatically removed
		1719	when the C<$scalar> is destroyed, or when the C<IO::AIO::mmap> or
		1720	C<IO::AIO::munmap> functions are called.
		1721
		1722	This calls the C<mmap>(2) function internally. See your system's manual
		1723	page for details on the C<$length>, C<$prot> and C<$flags> parameters.
		1724
		1725	The C<$length> must be larger than zero and smaller than the actual
		1726	filesize.
		1727
		1728	C<$prot> is a combination of C<IO::AIO::PROT_NONE>, C<IO::AIO::PROT_EXEC>,
		1729	C<IO::AIO::PROT_READ> and/or C<IO::AIO::PROT_WRITE>,
		1730
		1731	C<$flags> can be a combination of C<IO::AIO::MAP_SHARED> or
		1732	C<IO::AIO::MAP_PRIVATE>, or a number of system-specific flags (when
		1733	not available, the are defined as 0): C<IO::AIO::MAP_ANONYMOUS>
		1734	(which is set to C<MAP_ANON> if your system only provides this
		1735	constant), C<IO::AIO::MAP_HUGETLB>, C<IO::AIO::MAP_LOCKED>,
		1736	C<IO::AIO::MAP_NORESERVE>, C<IO::AIO::MAP_POPULATE> or
		1737	C<IO::AIO::MAP_NONBLOCK>
		1738
		1739	If C<$fh> is C<undef>, then a file descriptor of C<-1> is passed.
		1740
		1741	C<$offset> is the offset from the start of the file - it generally must be
		1742	a multiple of C<IO::AIO::PAGESIZE> and defaults to C<0>.
		1743
		1744	Example:
		1745
		1746	use Digest::MD5;
		1747	use IO::AIO;
		1748
		1749	open my $fh, "<verybigfile"
		1750	or die "$!";
		1751
		1752	IO::AIO::mmap my $data, -s $fh, IO::AIO::PROT_READ, IO::AIO::MAP_SHARED, $fh
		1753	or die "verybigfile: $!";
		1754
		1755	my $fast_md5 = md5 $data;
		1756
		1757	=item IO::AIO::munmap $scalar
		1758
		1759	Removes a previous mmap and undefines the C<$scalar>.
		1760
		1761	=item IO::AIO::munlock $scalar, $offset = 0, $length = undef
		1762
		1763	Calls the C<munlock> function, undoing the effects of a previous
		1764	C<aio_mlock> call (see its description for details).
		1765
		1766	=item IO::AIO::munlockall
		1767
		1768	Calls the C<munlockall> function.
		1769
		1770	On systems that do not implement C<munlockall>, this function returns
		1771	ENOSYS, otherwise the return value of C<munlockall>.
		1772
1429	=back	1773	=back
1430		1774
1431	=cut	1775	=cut
1432		1776
1433	min_parallel 8;	1777	min_parallel 8;
1434		1778
1435	END { flush }	1779	END { flush }
1436		1780
1437	1;	1781	1;
1438		1782
		1783	=head1 EVENT LOOP INTEGRATION
		1784
		1785	It is recommended to use L<AnyEvent::AIO> to integrate IO::AIO
		1786	automatically into many event loops:
		1787
		1788	# AnyEvent integration (EV, Event, Glib, Tk, POE, urxvt, pureperl...)
		1789	use AnyEvent::AIO;
		1790
		1791	You can also integrate IO::AIO manually into many event loops, here are
		1792	some examples of how to do this:
		1793
		1794	# EV integration
		1795	my $aio_w = EV::io IO::AIO::poll_fileno, EV::READ, \&IO::AIO::poll_cb;
		1796
		1797	# Event integration
		1798	Event->io (fd => IO::AIO::poll_fileno,
		1799	poll => 'r',
		1800	cb => \&IO::AIO::poll_cb);
		1801
		1802	# Glib/Gtk2 integration
		1803	add_watch Glib::IO IO::AIO::poll_fileno,
		1804	in => sub { IO::AIO::poll_cb; 1 };
		1805
		1806	# Tk integration
		1807	Tk::Event::IO->fileevent (IO::AIO::poll_fileno, "",
		1808	readable => \&IO::AIO::poll_cb);
		1809
		1810	# Danga::Socket integration
		1811	Danga::Socket->AddOtherFds (IO::AIO::poll_fileno =>
		1812	\&IO::AIO::poll_cb);
		1813
1439	=head2 FORK BEHAVIOUR	1814	=head2 FORK BEHAVIOUR
1440		1815
1441	This module should do "the right thing" when the process using it forks:	1816	Usage of pthreads in a program changes the semantics of fork
		1817	considerably. Specifically, only async-safe functions can be called after
		1818	fork. Perl doesn't know about this, so in general, you cannot call fork
		1819	with defined behaviour in perl if pthreads are involved. IO::AIO uses
		1820	pthreads, so this applies, but many other extensions and (for inexplicable
		1821	reasons) perl itself often is linked against pthreads, so this limitation
		1822	applies to quite a lot of perls.
1442		1823
1443	Before the fork, IO::AIO enters a quiescent state where no requests	1824	This module no longer tries to fight your OS, or POSIX. That means IO::AIO
1444	can be added in other threads and no results will be processed. After	1825	only works in the process that loaded it. Forking is fully supported, but
1445	the fork the parent simply leaves the quiescent state and continues	1826	using IO::AIO in the child is not.
1446	request/result processing, while the child frees the request/result queue
1447	(so that the requests started before the fork will only be handled in the
1448	parent). Threads will be started on demand until the limit set in the
1449	parent process has been reached again.
1450		1827
1451	In short: the parent will, after a short pause, continue as if fork had	1828	You might get around by not I<using> IO::AIO before (or after)
1452	not been called, while the child will act as if IO::AIO has not been used	1829	forking. You could also try to call the L<IO::AIO::reinit> function in the
1453	yet.	1830	child:
		1831
		1832	=over 4
		1833
		1834	=item IO::AIO::reinit
		1835
		1836	Abandons all current requests and I/O threads and simply reinitialises all
		1837	data structures. This is not an operation supported by any standards, but
		1838	happens to work on GNU/Linux and some newer BSD systems.
		1839
		1840	The only reasonable use for this function is to call it after forking, if
		1841	C<IO::AIO> was used in the parent. Calling it while IO::AIO is active in
		1842	the process will result in undefined behaviour. Calling it at any time
		1843	will also result in any undefined (by POSIX) behaviour.
		1844
		1845	=back
1454		1846
1455	=head2 MEMORY USAGE	1847	=head2 MEMORY USAGE
1456		1848
1457	Per-request usage:	1849	Per-request usage:
1458		1850

Diff Legend

-–
+Removed lines
-+
+Added lines
-<
+Changed lines
->
+Changed lines

Comparing IO-AIO/AIO.pm (file contents): Revision 1.165 by root, Tue Aug 18 04:05:00 2009 UTC vs. Revision 1.208 by root, Mon Sep 26 20:19:08 2011 UTC

Diff Legend

Comparing IO-AIO/AIO.pm (file contents):
Revision 1.165 by root, Tue Aug 18 04:05:00 2009 UTC vs.
Revision 1.208 by root, Mon Sep 26 20:19:08 2011 UTC